WRONG STUFF: David Wright (pictured) shows the frustration of the Mets’ fourth straight loss, 5-1 to the Phillies yesterday in a game that included poor hitting, weak relief pitching. Photo: Christopher Pasatieri

A crucial error by catcher John Buck (left) that allowed Ryan Howard (right) to spark a three-run seventh for Philadelphia. (AP)

WRONG STUFF: David Wright shows the frustration of the Mets’ fourth straight loss, 5-1 to the Phillies yesterday in a game that included poor hitting, weak relief pitching, and a crucial error by catcher John Buck (inset, left) that allowed Ryan Howard (inset, right) to spark a three-run seventh for Philadelphia. (
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The fact the losing pitcher was the closest thing the Mets had to a bright spot yesterday shows just how things are going in Flushing these days. Jon Niese was betrayed by a struggling lineup, shaky defense and sorry bullpen, all culpable in a 5-1 loss to Philadelphia that ran the Mets’ season-high losing streak to four.

Want to put a number on their misery? Three: As in getting held to only three hits, making three errors and mustering just three wins in a nine-game homestand. Want to put an image to their malaise? Try John Buck’s two-out error in the seventh, which opened the door for Ryan Howard’s two-run double off Scott Atchison that broke a 1-1 tie — and the Mets’ collective backs.

Niese matched Cole Hamels (1-3) in a pitchers’ duel until giving up two-out singles to pinch-hitter Laynce Nix and Jimmy Rollins in the seventh. When manager Terry Collins went to the righty Atchison, Phillies manager brought Howard off the bench. And when Atchison fell behind 2-0 and had to challenge Howard, the slugger drilled a 92 mph cutter off the fence in center field to bring home both runners for a 3-1 lead.

Chase Utley singled to left on the next pitch to make it 4-1. The way the Mets have been hitting, it might as well have been 14-1.

“I was trying to make a good pitch low and away on 2-0 and I didn’t do it. I didn’t execute the pitch. I wanted to pick up Jon right there, get us out of that inning and I didn’t execute,’’ said Atchison. “I didn’t execute. I left it back over the middle. He’s a good hitter and made me pay.’’

Niese, who had left his last start after just 2 1/3 innings after being hit on the leg by a comebacker, paid for the Mets’ leaky defense and cold bats. He threw 6 2/3 strong innings, but gave up two unearned runs, thanks to Buck’s error.

“It comes down to we didn’t support him. … We just didn’t get it done [offensively] and it showed,’’ said Buck, who had a long run toward the Phillies’ dugout in foul territory to even get a glove on Nix’s popup. “It hit my glove. I should’ve caught it. Anything that hits my glove, I should be able to catch it.’’

But Buck couldn’t catch it, and Niese couldn’t stop Nix from singling to left or Rollins from singling to center to end his day after 117 pitches.

“I did my best to pick [Buck] up there and unfortunately I wasn’t able to do that,’’ said Niese (2-2). “I didn’t want to [leave]. … My pitch count was up there. The situation called for it. But I definitely wanted to be in there.’’

Instead, Collins turned to Atchison and then Brandon Lyon, who allowed another run in the eighth. The Mets’ cold bats never threatened to come back.

The Mets have managed five or fewer hits in five of their last seven games, hitting just .186 with 81 strikeouts on a 3-6 homestand. They are now headed on the road to Miami and Atlanta.

“We just didn’t hit. Right now we’ve hit a slump offensively. We’re still in April. We’ll pick it up,’’ said Collins. “This is a game of ups and downs. Right now we’re in a down time. Well, you’ve got to forget about it. It’s hard, but you’ve gotta pick yourself up.’’